.sk_circle {
  margin: 100px auto;
  width: 40px;
  height: 40px;
  position: relative;
}

.sk_circle .sk_child {
  width: 100%;
  height: 100%;
  position: absolute;
  left: 0;
  top: 0;
}

.sk_circle .sk_child:before {
  content: '';
  display: block;
  margin: 0 auto;
  width: 15%;
  height: 15%;
  background-color: #333;
  border-radius: 100%;
  -webkit-animation: sk_circleBounceDelay 1.2s infinite ease-in-out both;
          animation: sk_circleBounceDelay 1.2s infinite ease-in-out both;
}

.sk_circle .sk_circle2 {
  -webkit-transform: rotate(30deg);
      -ms-transform: rotate(30deg);
          transform: rotate(30deg);
}

.sk_circle .sk_circle3 {
  -webkit-transform: rotate(60deg);
      -ms-transform: rotate(60deg);
          transform: rotate(60deg);
}

.sk_circle .sk_circle4 {
  -webkit-transform: rotate(90deg);
      -ms-transform: rotate(90deg);
          transform: rotate(90deg);
}

.sk_circle .sk_circle5 {
  -webkit-transform: rotate(120deg);
      -ms-transform: rotate(120deg);
          transform: rotate(120deg);
}

.sk_circle .sk_circle6 {
  -webkit-transform: rotate(150deg);
      -ms-transform: rotate(150deg);
          transform: rotate(150deg);
}

.sk_circle .sk_circle7 {
  -webkit-transform: rotate(180deg);
      -ms-transform: rotate(180deg);
          transform: rotate(180deg);
}

.sk_circle .sk_circle8 {
  -webkit-transform: rotate(210deg);
      -ms-transform: rotate(210deg);
          transform: rotate(210deg);
}

.sk_circle .sk_circle9 {
  -webkit-transform: rotate(240deg);
      -ms-transform: rotate(240deg);
          transform: rotate(240deg);
}

.sk_circle .sk_circle10 {
  -webkit-transform: rotate(270deg);
      -ms-transform: rotate(270deg);
          transform: rotate(270deg); }

.sk_circle .sk_circle11 {
  -webkit-transform: rotate(300deg);
      -ms-transform: rotate(300deg);
          transform: rotate(300deg);
}

.sk_circle .sk_circle12 {
  -webkit-transform: rotate(330deg);
      -ms-transform: rotate(330deg);
          transform: rotate(330deg); }

.sk_circle .sk_circle2:before {
  -webkit-animation-delay: -1.1s;
          animation-delay: -1.1s;
}

.sk_circle .sk_circle3:before {
  -webkit-animation-delay: -1s;
          animation-delay: -1s;
}

.sk_circle .sk_circle4:before {
  -webkit-animation-delay: -0.9s;
          animation-delay: -0.9s;
}

.sk_circle .sk_circle5:before {
  -webkit-animation-delay: -0.8s;
          animation-delay: -0.8s;
}

.sk_circle .sk_circle6:before {
  -webkit-animation-delay: -0.7s;
          animation-delay: -0.7s;
}

.sk_circle .sk_circle7:before {
  -webkit-animation-delay: -0.6s;
          animation-delay: -0.6s;
}

.sk_circle .sk_circle8:before {
  -webkit-animation-delay: -0.5s;
          animation-delay: -0.5s;
}

.sk_circle .sk_circle9:before {
  -webkit-animation-delay: -0.4s;
          animation-delay: -0.4s;
}

.sk_circle .sk_circle10:before {
  -webkit-animation-delay: -0.3s;
          animation-delay: -0.3s;
}

.sk_circle .sk_circle11:before {
  -webkit-animation-delay: -0.2s;
          animation-delay: -0.2s;
}

.sk_circle .sk_circle12:before {
  -webkit-animation-delay: -0.1s;
          animation-delay: -0.1s;
}

@-webkit-keyframes sk_circleBounceDelay {
  0%, 80%, 100% {
    -webkit-transform: scale(0);
            transform: scale(0);
  } 40% {
    -webkit-transform: scale(1);
            transform: scale(1);
  }
}

@keyframes sk_circleBounceDelay {
  0%, 80%, 100% {
    -webkit-transform: scale(0);
            transform: scale(0);
  } 40% {
    -webkit-transform: scale(1);
            transform: scale(1);
  }
}